# Homework Help: Laws of Motion with Static Equilibrium

1. Feb 12, 2010

### Keithkent09

1. The problem statement, all variables and given/known data
Find θ and W in the figure below where w1 = 16.0 N, w2 = 25.0 N, and α = 66.5°, assuming that the arrangement is at rest.

2. Relevant equations
T_1=25/sin(alpha)
F_x=-T_1cos(alpha)+T_2cos(theta)
F_y=T_1sin(alpha)+T_2sin(theta)-2

3. The attempt at a solution
I tried to use the above equations to solve for the three unknowns. First I found the tension of the string on the left, then plugged that into the second two equations to find the remaining values and I could not get the correct answers.

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2. Feb 12, 2010

### kuruman

Why is this true? What are tensions T1 and T2 in each rope?

3. Feb 12, 2010

### Keithkent09

Sorry I meant that it is 16/sin(alpha).
This is because the vertical component of T_1 is 16 because of w_1. So using trig T_1=17.447. I am doing this the correct way and just making some kind of simple mistake?

4. Feb 12, 2010

### kuruman

A pulley changes the direction of the tension without changing its magnitude. What is the tension in the piece of the leftmost rope that is hanging straight down?